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As research on parallel mechanisms with limited degrees of freedom (DOF) continues to grow, this paper introduces a novel 2UPU-2SPU parallel mechanism that features 2 Rotational and 2 Translational (2R2T) motion capabilities. The SPU branches are symmetrically positioned relative to the plane of the 2UPU branches, endowing the mechanism with a full-circle DOF that encompasses two rotations and two translations. One of the rotational DOF influences the characteristics of a constrained rotational freedom. This study conducts a kinematic analysis using screw theory to elucidate the DOF and derives the inverse kinematics of the mechanism. Furthermore, by employing motion/force transmission performance indicators and performance maps, the mechanical performance characteristics are analyzed. A mathematical model for optimizing mechanical performance using the Particle Swarm Optimization (PSO) algorithm is established, facilitating the design of specific mechanical devices. The mechanism boasts a large workspace, with the operational space varying as the moving platform rotates, making it suitable for applications requiring minimal rotational and lateral movements but significant longitudinal displacement. [ABSTRACT FROM AUTHOR]

Laparoscopic manipulation of delicate large intra-abdominal organs is a difficult task that needs special training programs to improve the surgeons' dexterity. In this study, the mechanical design of a robotic interface for haptic simulation of largeorgan laparoscopic surgery is described. The designed robot enjoys active active Degree of Freedoms (DOFs), back drivability, low inertia, friction and backlash, and sufficiently large force/moment production capacity. The kinematics of the robot was analyzed and a functional prototype was fabricated for experimental tests. Results indicated that the target workspace was fully covered with no singular points inside. The mechanism was highly isotropic and the torque requirements were in the acceptable range. The trajectory tracking experiments against a 1 kg payload revealed an Root Mean Square (RMS) of 0.9 mm, due to the simplifications of the kinematic model, i.e., not considering the friction and backlash effects. It was concluded that the designed robot could satisfy the mechanical requirements for being used as the robotic interface in a haptic large-organ laparoscopic surgery simulation system. [ABSTRACT FROM AUTHOR]

We aimed to systematically review and meta-analyze the association of employees working in various kinds of open-plan offices with sick leave data, compared to those working in traditional cell offices. Databases of PubMed, PubPsych, and Psyndex were systematically searched following the PRISMA statement. Pooled summary estimates of odds ratio (OR) were calculated comparing sick leave of employees in cell offices with those working in small open-plan offices (4-9 people), and those in various open-plan office solutions (>4 people). We used Forest plots visualizing study-specific estimates and the pooled fixed and random effects estimators. Five studies were identified (2008-2020) with a total of 13,277 (range 469-6,328) participants. Compared with employees working in cell offices, those working in small open-plan offices were associated with higher odds of sick leave days (OR=1.27; 95% CI 0.99-1.54; p=0.046) as well as those working in various kinds of open-plan offices with >4 colleagues (OR=1.24; 95% CI 0.96-1.51; p=0.004). Our results are consistent with those of earlier reviews focusing on other effects of open-plan office solutions such as health and well-being. Different solutions for office design and architectural lay-out should be the focus of future studies to balance pros and cons of open-plan offices. [ABSTRACT FROM AUTHOR]

An autonomous solar powered lawn mower deployable to a pre-mapped area was developed. The device receives directional sense using Mission Planner for pre-mapping of the workspace. This gives the device full control over the desired workspace, helping it to maneuver obstacles, including stones and trees, and get the work done without human intervention. The Autonomous device is made up of a robotic chassis, having four wheels and a DC motor connected to its underside, which is used to move the cutting blade. The blade cuts the grass beneath the lawn mower as the device navigates the workspace. Two microcontrollers were used to achieve the automation of this device. The first microcontroller was used to achieve obstacle avoidance while the second complimentary microcontroller was used to navigate the workspace autonomously. Holybro Kakute F7 HDV serves as the system central processing unit and it uses the Ardupilot technology to achieve navigation. It is particularly optimized for rovers due to its high resistance to vibration, ruggedness and size. A prototype of the robotic mower was developed and its operational performance satisfactory. The size of the pre-mapped area can vary, but a total distance of 135m was covered for the testing that was done. [ABSTRACT FROM AUTHOR]

In this study, a Floating Parallel Marine Robot (FPMR) is studied while it is subjected to external forces generated by the sea waves. Two FPMR cable-bundles' configurations are used. The 6–6 Stewart-Gough parallel manipulator configuration is compared with a new cable-bundles' configuration called 6–3-3 FPMR. The effect of changing cable-bundles' configuration is explored to enhance the workspace and the dynamic behavior of the FPMR. This study is performed using six DOFs FPMR having twelve cables i.e. 6 bundles. Over the FPMR workspace, the dynamic response and platform stiffness are investigated. The workspace and the dynamic analysis of FPMR are enhanced using the new 6–3-3 cable-bundles' configuration. [ABSTRACT FROM AUTHOR]

In recent years, creativity has become a major focus in organizations competing to develop new products and offer new solutions to the community. Since then, the achitectural firms' workplace have been extensively studied as well as modified to support user creativity, productivity, and satisfaction by offering unique environments that create a social space which encourages collaboration, inspiration, and motivation. These changes are a response to the new connection employees have with their surroundings and how the spatial design facilitates the users' work performance and process. This new focus has played a major role in insuring the organizations' creative success and attracting selective employees. Investigation into the development of the office workplace designs reveals that certain spatial design features have been documented to have different effects on users. Spatial designs features such as colors, light, layout, furniture, plants, etc. become specific components that designers use to construct the workplace. By studying the layout qualities, tangible an intangible elements that compose the spatial environment in three architecture firms, this paper aims to investigate how the spatial design affects the users and how designers can improve the users' workplace experience through observations, interviews and questionnaires. A Post occupancy evaluation reveals that there are certain key features that designers and organizations must consider when designing new workplace environments for creative users. [ABSTRACT FROM AUTHOR]

The article deals with the problem of optimization of parameters 6-6 UPU of the mobility platform using the Particle Swarm Optimization (PSO) algorithm. The optimization criterion is based on minimizing the dimensions of the structure, taking into account the required relationships between some parameters. The limitation of optimization is the condition of providing the required workspace, taking into account the platform orientation ranges. An algorithm for calculating the estimate of the occurrence of the required area in the workspace of the platform with given parameters is synthesized. Workspaces specified as an ordered set of integers. The results of mathematical modeling are presented. [ABSTRACT FROM AUTHOR]

In this study, the mathematical analysis and design of a new 3D printer with 5 degrees of freedom were carried out. Thanks to the developed system, a new concept has been brought to the multi-axis 3D printer mechanisms, and thus, it is aimed to improve the part quality in additive manufacturing (AM) processes. As a result of adding the 4th and 5th axes to the moving platform of the system, the production time of the part was accelerated. It is also possible to print more complex and curved shapes with less support. To design a system with these features, first of all, the kinematic analysis of the system was obtained using vector algebra, and the workspace of the current printer was determined by considering the system constraints in this article. By giving detailed information about the mechanical and electrical components of the designed system, the working principle of the whole system is presented. According to the findings obtained in the studies, the kinematic analyses performed for the proposed system proved to be correct and a new system was proposed especially for additive manufacturing technologies. [ABSTRACT FROM AUTHOR]

Robot simulation is an important way to verify the correctness of model and feasibility of design. Taking the Delta parallel mechanism as the effector of a weeding robot, this paper designs the workspace for the weeding mechanism in the field of corn seedlings, when each corn seedling has three to five leaves, and then carries out a simulation analysis on the workspace of the weeding mechanism. To realize variable rate precision spraying, the authors planned a three-segment gate-shaped trajectory for the end effector, detailed the trajectory under the joint coordinate system, and analyzed the motion law of S-curve motion profile. Then, the law of each kinematics parameter was solved on MATLAB, and plotted into graphs. Based on the simulation results, a prototype was developed for the proposed weeding mechanism, and subject to weeding experiments to obtain the end effector trajectory. Compared with the simulated results, the maximum deviation in the end effector trajectory during actual operation was 11.58%; the prototype could complete a weeding action every 2.8 s, while advancing at the speed of 0.4 m/s. The results fully demonstrate the feasibility of applying Delta parallel mechanism in weeding, and the reasonability of our workspace design and trajectory planning. [ABSTRACT FROM AUTHOR]

Multi-robotic systems are used to solve many practical tasks in wide areas, including military surveillance, reconnaissance, rescue operations, warehousing, etc. Such systems can be represented as groups of intelligent robots capable of interacting with each other and jointly implementing various tasks. One of the problems in the development of such systems is the safe navigation of a group of robots. The restrictions imposed by the structural elements of its agents are determined to solve it. The article presents the structure of a multi-robotic system consisting of parallel and serial robots installed on mobile platforms. The parallel robot is made based on a tripod with the possibility of rotating the robot base about the horizontal axis. Determining the workspace boundaries of robots eliminates collisions between agents and external objects. The developed algorithms are based on deterministic methods for approximating the solutions set of nonlinear inequalities systems with restrictions in spaces of coordinates in the form of n-dimensional boxes. The relative positions of mobile platforms with manipulators, at which collisions are possible, are determined. [ABSTRACT FROM AUTHOR]

Copyright of Megaron is the property of KARE Publishing and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Supplemental digital content is available in the text. Background: The COVID-19 pandemic and subsequent social distancing guidelines greatly impacted the quality of life (QoL) of nursing faculty. Purpose: The purpose of this study was to examine the relationship of QoL, resilience, and associated factors among nursing faculty during the COVID-19 pandemic. Methods: In April 2020, a cross-sectional, anonymous survey was conducted with nursing faculty in a public university in rural Appalachia (n = 52). Instruments included QoL, resilience scales, work-related, and demographic variables. Descriptive, bivariate, and multiple linear regression analyses were used to analyze data. A content analysis was used to analyze an open-ended question. Results: Resilience was the strongest variable to predict each of the QoL domains. Nursing faculty who reported better QoL were those who were able to adapt to changes and challenges mandated during the COVID-19 pandemic. Conclusions: Evidence-based programs to build resilience and improve nursing faculty working conditions and their QoL are needed. [ABSTRACT FROM AUTHOR]

The Ortho-SUV frame, a novel external fixator, can effectively treat limb deformities and fractures. Its kinematics is used when it is necessary to achieve bone movements with high precision. In this work, the kinematics model of the Ortho-SUV frame is established by six pose parameters, and its forward and inverse solutions are given. There is no need to solve nonlinear high-coupling equations with trigonometric functions in this solution method due to its special structure. By numerical examples and simulated orthopedic experiment of tibial fracture, the correctness and accuracy of the kinematics model and its solutions are verified. Besides, on the basis of kinematics analysis, the position workspace and orientation workspace of the Ortho-SUV frame are simulated in Matlab, which can help) surgeons choose suitable device dimensions. The kinematics analysis provides a theoretical basis for the Ortho-SUV frame to be used in orthopedic treatment. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian University of Technology / Dalian Ligong Daxue Xuebao is the property of Journal of Dalian University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cable-Driven Parallel Robots (CDPRs) are composed of a base frame and a moving-platform. A set of cables actuated by winches and guided by pulleys on the base frame are attached to the moving-platform. Those cables are used to generate motions or to apply forces to the moving-platform throughout its workspace. CDPRs are being increasingly used in industry due to several advantages provided by the cables such as a large translational workspace, a high payload-to-weight ratio and high velocities and accelerations. However since the cables can only pull the moving-platform, the latter cannot go out of the robot base frame bounded by the pulleys. An example is the treatment of large structures by using a CDPR. The structure itself can be used to hold the pulleys of the CDPR and the moving-platform would therefore need to go out of the robot volume to reach it. To overcome this issue a grasping device is mounted onto the moving-platform to grab the structure. It should be noted that when the structure is grabbed, the model of the overall system changes as the motions of the moving-platform is not only controlled by cables anymore, but the contact between the grasping device and the structure should be considered. This paper deals with the conceptual design of a grasping device for CDPRs and the definition of two workspaces. The first workspace characterize the area covered by the moving-platform when the latter is free of contact with the environment. The second workspace is the region that the gripper can follow during gripping phase. It turns out that the robot workspace increases while considering the structure grasping into the system modeling. [ABSTRACT FROM AUTHOR]

This paper presents an explicit work on developing a parallel manipulator for medical application. There are many applications in medicine that requires the technology of robotics like injecting electrodes, drilling of bone, medical transportation, to carry out different tests and so on. Surgeons divert their focus on improving the quality of the surgical procedure that includes accuracy, security, low morbidity and mortality. This work mainly concentrates on designing and developing a kinematic and dynamic model of parallel manipulator for bone drilling application which is required for prosthetics operations. According to the requirement of the application a three prismatic-universal-universal (3PUU) parallel manipulator is designed which rotates about x and y axis and translates along z axis. This research work involves in developing a conceptual design, deriving kinematics both inverse and forward, workspace and dynamics of the parallel manipulator. Inverse kinematics is obtained by the geometrical approach whereas inverse dynamics is obtained using Langrangian method. Further, the tool inverse kinematic solutions, overall workspace, dynamics of the three legs are determined. This study will help the researchers for the further development of parallel manipulators in medical assistance. [ABSTRACT FROM AUTHOR]

From the mere presence of plants to window views of nearby nature, contact with nature in the workplace has been associated with increased productivity and creativity, as well as positive emotional and physical health outcomes. Nevertheless, if nature is to be incorporated within or near workplaces effectively, it is important that workers perceive natural spaces to be conducive, and not detrimental, to performance on activities that they may engage in at work or else these changes to the physical environment may not be fully embraced by workers. Thus, in the current research we examine workers’ preferences and perceptions of different natural and constructed (built) environments for different workplace activities. In Study 1, 64 knowledge workers were exposed to images of natural outdoor and constructed indoor workspaces. They selected where they thought they would best and least be able to perform different workplace activities. Natural outdoor spaces were overrepresented as the best spaces for around 75% of the workplace activities, and were underrepresented as the worst spaces across all workplace activities. In Study 2 ( N = 33), wherein participants evaluated various spatial qualities of the natural outdoor and constructed indoor space types that were included in Study 1, the natural outdoor spaces were rated as more fascinating, relaxing, open, bright, and quiet. The results of this research project suggest that natural outdoor workspaces are viewed as highly flexible, multi-use spaces that are appropriate for diverse workplace activities. Furthermore, access to diverse workspace types with different spatial qualities appears to be highly valued. [ABSTRACT FROM AUTHOR]

The specific aim of this article is to illustrate a possible model to explain and better define in future, the emergence of a conscience like ability from the normal brain operations. We consider the normal behavior of the brain to be highly dynamic and use the chaos theory to formalize it. The emergence mechanism is explained in terms of the synchronization and filtering capabilities of the single computational units (from single neurons to specific brain regions). To obtain such results we suggest the use of the filtering operation as a read/write operation that uses the unstable dynamics as a distributed processing and memorization device. The main focus of this article, though, is only on the read operation. These mechanisms provides the basic building block to go from an unconscious, purely biological and physical, behavior to a pre-conscious (“core consciousness”) one in which the single elements of the conscious perception can be altered according to a specific target that can violate the underlying biological/physical laws. In other words, it is possible to define the emergence of the basic building block of the conscious behavior (qualia?): that is the simultaneous presence of the elements from different perceptual systems (vision, tact, smell etc.). These lists of simultaneously present elements, that changes in time according to the interaction with the external world, form the lists of elements to be brought in a Global Workspace Theory based system. [ABSTRACT FROM AUTHOR]

In minimally invasive robotic surgery (MIRS), a surgeon teleoperates a robotic arm from a master console. This arm operates inside the patient's body through a small orifice which constrains the end-effector's translation along two axes. The workspace of such a robotic arm depends on its design as well as orifice location. Conventionally, the design of such an arm is optimized for large workspace and high dexterity. However, this large workspace might be reachable through only a few orifices, thus making the workspace volume and operation quite sensitive to the orifice location. To overcome this problem, we optimized the design of a 3 degrees of freedom serial robotic arm to attain multiple adjacent (desired number of) possible orifice locations, through which a planar workspace of pre-specified geometry can be traced. To achieve this goal, an algorithm was developed to relate the design of such an MIRS arm to the possible orifice positions. The optimization problem was solved using several metaheuristics such as simulated annealing, Tabu search, artificial bee colonization and genetic algorithm, and their performance was compared. [ABSTRACT FROM AUTHOR]

The structure of a novel 5-DOF industrial manipulator was analyzed. The homogeneous transformation matrix of the manipulator was obtained by establishing a series of D-H frames. Based on Paul's inverse transformation, an analytical method that could direct the solution of inverse kinematics problems of series manipulators was proposed, and the closed-form solution of inverse kinematics was derived. Computational simulation results indicated that the algorithm was efficient and real-time. The enveloping surface of the local joints' workspace was specified using envelop theory. Working dexterity of the manipulator was discussed. The dexterous workspace of the manipulator on which the structure design and motion control were based was established via geometrically overlaying the enveloping surfaces of local joints' workspace. [ABSTRACT FROM AUTHOR]

The article presents a study investigating the comfort aspects of the agricultural tractor workspace interior and presents the views of several operators about the comfort level. It was found that layout of the seat, accessories and controls can affect the operator's perceived comfort. It also provides several guidance for improving the comfort of tractor workspace interiors.

This paper introduces a sort of cord-type haptic interaction device, and presents two methods to analyze its haptic workspace restricted by the maximum tension of strings. By using the proposed methods, multi-level haptic workspaces of the 3-DOF haptic device were drawn. The results show that the higher level of the haptic device the smaller volume of the workspace. For the devices with same level, the workspace volume is directly proportional to the pull or distance of the motors. [ABSTRACT FROM AUTHOR]

Copyright of Ingenium is the property of Facultad de Ciencias Basicas e Ingenieria de Universidad de San Buenaventura, Revista Ingenium and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Detailed theoretical analyses are performed on dimensional synthesis of a 5 - DOF parallel mechanism with topological structure of 4 - UPS/UPU in this paper for providing the theoretical supports for engineering applications. Based on the kinematics analysis, a comprehensive method for the dimensional synthesis of such mechanism is developed for obtaining the optimal kinematics performance within the prescribed task workspace. Firstly, the independent design variables are divided into two categories: structural angles and geometrical parameters. Then the effects of dimensional parameters on the kinematics performance are reviewed through a thorough monotonous analysis, and the optimal solution set of structural angles is defined. Subsequently, the geometrical parameters of such mechanism are achieved by optimizing a compound objective index subjected to a set of appropriate mechanical constraints. A numerical example shows that the proposed method is effective and is significant for some other similar parallel mechanisms. [ABSTRACT FROM AUTHOR]

A novel multifingered metamorphic hand is analyzed. This hand differs from the previous robotic hands in that the palm is moveable. The reconfiguration of the palm enhances the dexterities and the workspace of the hand. When the linkages of the palm stand still, each finger operates in a plane. Hence the finger operation plane is introduced so that the orientation analysis of the hand can be explored by investigating the motion of the unit vectors of the three finger-operation planes. The three unit vectors can be obtained by coordinate transformation in a global coordinate system and are mapped to orientation ruled surfaces. Next, three common poses of grasping with finger-tips are .analyzed and the conditions for the palm to realize these three poses are obtained. The design of the palm is converted into that of solving a nonlinear equation system with 11 equations and 12 variables. The satisfactory numerical solution of the nonlinear equation system is obtained. Finally three-dimensional simulations of the multifingered hand based on the above numerical solution are made to verify the correctness of the computation. [ABSTRACT FROM AUTHOR]

To shape the workspace of some novel parallel manipulators (PMs) is significant. A novel computer-aided design (CAD) variation geometry approach is proposed to shape and solve the reachable workspace of some PMs with three to six degrees of freedom (DOFs). Some basic techniques are described for designing the simulation mechanism and solving the reachable workspace. The simulation mechanisms of some PMs with three to six DOFs are created. When varying the driving dimensions of the active legs in the given extent, the simulation mechanisms vary correspondingly, and the position components of the moving platform are solved automatically. By transferring the position solutions into spatial spline curves in the simulation mechanism, all the boundary surfaces of the workspace can be created and visualized dynamically. Comparing with analytic approaches for solving workspace, the CAD variation geometry approach is simple, straightforward, accurate, and repeatable. [ABSTRACT FROM AUTHOR]

A novel 3-RRPRR parallel manipulator with three pure translational movements and a relative larger workspace is proposed. Its three isomeric mechanisms 3-RRPU, 3-RPRU, and 3-UPU with three pure translational movements are constructed by varying dimensions of some links. Their common kinematic characteristics, workspace, and singularity are analysed, the active force and the constrained torque are solved. First, a simulation mechanism of the 3-RRPRR manipulator is created, and its kinematics, singularity, and workspace are analysed by using an analytical approach and a computer-aided design (CAD) variation geometry approach. Second, the common analytical formulae for solving the displacement, velocity, and acceleration of the four manipulators are derived. Third, the formulae for solving the active forces and constrained torques of the 3-RRPRR manipulator are derived. The analytic-solved results are verified by their simulation mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, the design and kinematic performances are presented for a parallel manipulator with four driven cables. Kinetostatic analysis has been performed for both planar and spatial operations of the manipulator as based on a geometrical approach. A low-cost prototype has been built and an application is proposed to show the feasibility of the system design and its operation. [ABSTRACT FROM AUTHOR]

The aim of this study is to present a new model to extend the workspace of a parallel working machine in a chosen direction. Therefore, the existing mathematical models are combined and developed to represent the extension of the workspace of a 6° parallel working machine. For this purpose, the 6-3 Stewart platform mechanism (SPM), which is commonly used in robotic applications, material processing, and flight simulation, and the 6-4 SPM have been chosen. Although there are many studies on parallel mechanisms, the workspace analysis of a parallel working mechanism has not yet been generalized. This study determines the workspace of a parallel working mechanism in the direction perpendicular to the moving platform, which is the most workable direction. For these types of working mechanisms, i.e. mechanical tools used for material processing that is forced to move in a certain chosen direction, the determination of the point in that direction at which the workspace is maximum has to be outlined. After carrying out a kinematic analysis, the discretization method, which is based on Euler angles, is used to represent the orientation workspace of these parallel working mechanisms. Additionally, the orientation workspaces of the 6-3 SPM and the 6-4 SPM are compared. Results are presented in a cylindrical coordinate system. [ABSTRACT FROM AUTHOR]

Inquiry into how people experience environmental conditions at work is a growing area of study. Until the 1980s, there was insufficient research on 'workspaces' -and on office environments in particular -- to warrant review. Since that time, the range and number of studies of workspace have burgeoned. This paper will identify and review the main themes and findings of this area of research with the objective of defining basic parameters and prevailing theories of the environmental psychology of workspace. These will generate questions and directions for future research. [ABSTRACT FROM AUTHOR]

The environments and landscapes in which we live and work say much about who we are and how we act, yet there is little in the literature that considers Primary Care professionals' reflections on workspace and its impact on practice. The paper addresses this lacuna by presenting the findings of Phase II of a novel, two-year, mixed-methods study of UK General Practitioner (GP) workspace. Phase II employed photo-biographic-elicitation interviews supported by photobiographic data from Phase I, to examine 8 GPs' understandings of their workspace in relation to professional practice and self-identity. Through distillation and summation of datasets, the paper establishes the pivotal role of workspace in Primary Care. Unlike many qualitative studies, the paper emphasizes ambiguity and difference rather than certainty and similarity as characteristics that prove to be of major significance in understanding the particularity of GP workspace. Like CHAUCER's Canterbury Tales, GPs' individual stories are set as a sequence of tales within what might be called a frame narrative-the overarching narrative of British general practice providing the frame for the particular stories of the practitioners. Although working environments may be similarly structured, how GPs perceive, perform within, and move through their own setting is unique to each. [ABSTRACT FROM AUTHOR]

The public library is full of creative people. Many library employees flourish in library systems that encourage them to move forward with their creative muses. A scan of the blogosphere quickly proves the public library attracts many creative minds and innovative thinkers to join its ranks. Once they have signed on to serve, what do we do to keep these creative types inspired, dreaming and channeling this creative energy into crafting experiences that benefit our users? What are we doing to consciously create a workplace that keeps fresh thinkers and risk-takers encouraged and empowered? Gleaned from conversations, interviews (both in and outside the library), and the Youth & Outreach Services "Library in Action" blog (http:// libraryinaction.blogspot.com), this article discusses how workspace affects learning, temperament, production, and creativity in public libraries. [ABSTRACT FROM AUTHOR]

Workflows emphasize the partial order of activities, and the flow of data between activities. In contrast, cooperative processes emphasize the sharing of artefact, and its gradual evolution toward the final product, under the cooperative and concurrent activities of all the involved actors. This article contrasts workflow and cooperative processes and shows that they are more complementary than conflicting and that, provided some extensions, both approaches can fit into a single tool and formalism. This article presents Celine, a concurrent engineering tool that can also define and support classic workflows and software processes. We claim that the availability of both classes of features allows for the modeling and support of very flexible processes, closer to software engineering reality. Copyright © 2007 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

A new three-prismatic-revolute-cylindrical (three-PRC) translational parallel manipulator (TPM) with orthogonally arranged fixed actuators is proposed in this paper. The mobility of the manipulator is analysed via screw theory. The inverse kinematics, forward kinematics, and velocity analyses are performed and the singularities and isotropic configurations are identified afterwards. Moreover, the mechanism design rules producing a singularity-free manipulator have been generated. Under different cases of physical constraints subject to mechanical joints, the reachable workspace of the manipulator is geometrically determined and compared. In particular, it is illustrated that the manipulator has a regular shape workspace with a maximum cuboid defined as the usable workspace inscribed and one isotropic configuration involved. Furthermore, to obtain a large usable workspace, the architecture design of a three-PRC TPM is carried out and the singularity property within the usable workspace is verified. Simulation results show that there are no singular configuration within the workspace, which reveal the validity of design rules for a singularity-free three-PRC TPM. [ABSTRACT FROM AUTHOR]

In this paper a workspace and stiffness analysis for a two-degree of freedom parallel micro robot is outlined by using optimality criterion of workspace and numerical aspects. The variation tendency of stiffness within the workspace is presented and the impact of variation of design parameters on the stiffness characteristics is given, that is helpful for the architecture design of a 2-DOF parallel robot considering stiffness performance. We proposed a numerical procedure for determining and evaluating the workspace of the R̲R̲R robot architecture. The analysis and algorithm can be used as a design tool to select dimensions, actuators and joints in order to maximize the workspace and improve stiffness within the workspace. This paper provides a basis for the architectural design of the 2-DOF parallel robot with stiffness properties taken into account, which is necessary from the design point of view. [ABSTRACT FROM AUTHOR]

In this paper a mono-objective optimum design procedure for parallel robot is outlined by using optimality criterion of workspace and numerical aspects. A mono-objective optimization problem is formulated by referring to a basic performance of parallel robots. Additional objective functions can be used to extend the proposed design procedure to more general but specific design problems. A kinematic optimization was performed to maximize the workspace of the mini parallel robot. Optimization was performed using Genetic Algorithms. [ABSTRACT FROM AUTHOR]

A new type of three-dimensional parallel robot with a human interface as well as parallel motion control of a platform manipulator actuated by three a. c. servomotors is presented in this paper. The performance of this parallel robot is analysed using its forward and inverse kinematics. The analysis is performed using known quantified and graphical performance synthesis tools. Computer simulations of the parallel robot system have shown good correlation between physical interpretations and the results of using the theoretical analysis tools. [ABSTRACT FROM AUTHOR]

The specific aim of this study was to develop a quantitative method and a kinematic method to evaluate the maximal workspace of the trapeziometacarpal (TM) joint. Six fresh-frozen human cadaver hands were disarticulated 4 cm proximal to the wrist joint and used in this experiment. The three-dimensional motion data of the TM joint was collected by an electromagnetic tracking device at 30 Hz. The workspace was reconstructed according to a complete set of motion data included circumduction, flexion–extension and abduction–adduction. A spherical fitting technique was used to obtain a sphere encompassing all the motion trajectories and estimating the centre of the sphere. The surface area of the maximal TM workspace, located on the one part of the sphere surface, was calculated by surface integration. The interclass correlation coefficient values for the reliability estimation of the repeated measurements of the radius and surface area of all specimens were 0.91 and 0.98 respectively. The mean coefficients of variance of the measured radius and the surface area were 2.04 per cent and 3.65 per cent respectively. The results also showed that using a spherical model to calculate the maximal workspace as an index for assessing TM joint impairment is practical. [ABSTRACT FROM AUTHOR]

This paper presented a general method, which is used in solving the mobility condition of planar multi-loop and multi-DOF mechanisms by the mobility conditions and the workspaces of planar single-loop linkages. The method is suitable for both automated and manual analysis. The mobility of hybrid driven planar 2-DOF seven-bar mechanisms was analyzed. Firstly, the mobility of two five-bar mechanisms corresponding to the two five-bar closed-loop kinematics chains in the planar seven-bar linkage was analyzed, and the minimum dimension conditions for the existence of the cranks in the two five-bar mechanisms were obtained. Secondly, the workspaces of the two five bar linkages were analyzed, and the further restriction conditions for the mobility resalting from the coupling between the closed loops were obtained according to the workspace. Consequently, the mobility conditions were derived for the 2-DOF planar seven-bar mechanisms with three unconditional cranks. A practical seven-bar mechanism was given and simulated. [ABSTRACT FROM AUTHOR]

Parallel robots lead to complex kinematics equations, so determination of their workspaces is a challenging issue. The workspace of a robot is not fully characterized by its volume alone; the workspace shape is an important aspect as well. In this paper, the geometric determination of the workspace for Delta robots is presented. The workspace (workspace volume and workspace shape) for the robots is studied systematically in 'the physical model of the solution space', which is a useful tool to express relationships between the performance criteria and all link lengths of one type of robotic mechanism. Performance atlases of the workspace volume for the robots are plotted in the physical model of the solution space. The characteristics of the distribution of the workspace shapes in the physical model of the solution space are presented as well. The physical model of the solution space presents a new method for the computer aided design (CAD) of robotic mechanisms. The results are very useful for obtaining the optimum design of robotic mechanisms. [ABSTRACT FROM AUTHOR]

In this paper the design of a miniaturized parallel architecture is investigated in terms of basic performances concerning mobility and workspace characteristics. The miniature requirements have been achieved with a milli-scaled parallel manipulator requiring flexural joints and binary actuation with shape memory alloy wires or small pneumatic pistons. The mechanical design is analysed by considering the mobility of the flexural joints in order to size them and model the kinematics of the joints. The reachability is analysed through a suitable formulation of the direct kinematics by also taking into account binary actuation. Workspace performance has been determined in terms of position and orientation capabilities. [ABSTRACT FROM AUTHOR]

The parallel kinematic machine tool has many advantages including excellent loading capacity, high structural stiffness and small accumulated error of linkage. It has become one of the most important research fields for machine tools. In the present research, a principle for the optimization of the dimensional design parameters of a parallel kinematic machine tool is proposed. A five-degree-of-freedom (5DOF) parallel kinematic machine tool with a TRR-XY hybrid mechanism is chosen for investigating the design procedures and the optimization results. The inverse kinematics of the hybrid mechanism is first investigated. Then, the inverse solution is used to analyse and create the workspaces of the machine tool. The design parameters of the mechanical components are further optimized for constructing the maximum workspace. [ABSTRACT FROM AUTHOR]

• This study examines the influence of socioeconomic factors and household features on the adaptation of telework spaces for Madrid (Spain), during the confinement decreed at the beginning of the COVID-19 pandemic. • The socio-economic profile of teleworkers indicated a high level of studies, mostly salaried workers, a high level of average income, and therefore a privileged condition. • A third of the households considered their telework spaces as inadequate, being related to: the lack of exclusive spaces to work; be more than one teleworker per household; having poor digital resources; or to the inadequacy of the characteristics of such spaces. • Although this study contributes to evaluating households' perception of the adequacy of homes for teleworking in an unusual context, it may be helpful for future analysis of teleworking and those aspects in households that influence such perception. In Spain, the COVID-19 confinement was carried out in the spring of 2020. All non-essential activities were temporarily suspended. This brought with it the adaptation to home office (telework), still emerging in Europe, and more in Spain. Although the response in general has been positive, the conditions to which families have been subjected to telework cannot be considered normal. In this context, an online survey was requested to find out the experience of confined households in relation to the dwelling adaptation and satisfaction following the new needs in lockdown. The data obtained on workspace perception and its adequacy were studied in Madrid, stratified by gender and average income, for a sample of 256 households with people teleworking or studying. The results showed that the adequacy of telework spaces were insufficient for a third of the households, with no significant relationship with most of socioeconomic variables, nor with home characteristics. The variables related to this inadequacy of the spaces were: the number of people who work or study at home; the lack of exclusive spaces for teleworking; and the availability of digital resources. This perception also depended on the qualities of the teleworking space, as size, furniture and lighting, among others. [ABSTRACT FROM AUTHOR]

A machine's weight is directly related to the strength of the installed joint actuators, and it is reasonable to assume that minimizing the installed joint torques will minimize the machine weight. Unfortunately, the workspace area will also reduce with the installed joint torques; thus there must be a compromise between weight (joint strength) and workspace. Methods are presented to generate the set of static workspaces corresponding to a range of installed joint torques. In this way the relationship between the workspace area and installed joint torque can be established. A numerical example is presented which shows that a small reduction in the workspace area can lead to a substantial reduction in installed joint torque and hence machine weight. [ABSTRACT FROM AUTHOR]